Huu-ay-aht First Nations uses Innovative Technology and a Pipeline Rehabilitation Project

Huu-ay-aht First Nations

Innovative Technology and a Pipeline Rehabilitation Project

Project Assessment

Chatwin Engineering was successful in rehabilitating a strategic piece of pipe in the Huu-ay-aht First Nations water supply system, which was buried under the Pachena River.

PROJECT SCOPE

In 1985, Chatwin Engineering constructed a water supply and distribution piping system to supply a water storage reservoir in the higher land on their Reserve; this piping system was buried under the Pachena River.The pipe was made of ductile iron pipe and weighted down with large concrete blocks and buried beneath the Pachena River.

Planning & Analysis

This year the Huu-ay-aht First Nations constructed a new water storage reservoir at a higher elevation on private lands that they purchased adjacent to their Anacla Reserve.This higher reservoir put higher pressure on the Pachena River pipeline crossing, which created leaks in the older piping system.Digging up the pipe beneath the Pachena River to try and locate the leak was an expensive option.

Solution & Implementation

Chatwin Engineering proposed pulling a 3” diameter polyethylene pipe through the 4” diameter ductile iron pipe.Todd Wilson, P.Eng., the engineer for the project, said “we had no idea what condition the existing 4” ductile iron pipe was in and whether there had been any movement in the pipe, which could cause a restriction to sliding the new piping through it; so consequently there were sleepless nights over this procedure”.

Conclusion & Summary

On April 12, 2011, the contractor, Locar Developments was successful in pulling the 3” polyethylene line through the pipe to create the permanent fix. Brian Chatwin of Chatwin Engineering commented “We are ecstatic at the success of this operation, as now the Huu-ay-aht First Nations water crossing will be secured for the next 50 years”.